Programming apparatus



June 4, 1968 v, c, REES 3,387,115

PROGRAMMING APPARATUS Filed Oc t. 14, 1965 4 Sheets-Sheet 1 IN ENTORVERA/0N 6. 55

June 4, 1968 v, 3, R555 3,387,115

PROGRAMMING APPARATUS Filed Oct. 14, 1965 4 Sheets-Sheet 2 NORMALOPERATXNG TEMPE RATU RE 56 D E LIJ 54 Fig. 3

AMBIENT ME Big 4 1 4d Ir 5' v I j gg ur United States Patent M 3,387,115PROGRAMMING APPARATUS Vernon C. Rees, Newark, Ohio, assignor toOwens-Corning Fiberglas Corporation, a corporation of DelawareContinuation-impart of application Ser. No. 293,994,

July 10, 1963. This application Oct. 14, 1965, Ser. No..496,09 4

' 12 Claims. (Cl. 219-504) ABSTRACT OF THE DISCLOSURE 7 Programmingapparatus in which electrical signals are converted to heat which isaccumulated or-stored. Heat sensitive apparatus provides electricaloutput signals in response to the amount of heat so accumulated orstored to provide long term programming signals.

The present invention relatesto programming apparatus in general and, inparticular, to thermal programmers and time responsive integrating.units. This application is a continuation-in-part of'my co-pendingapplication Ser. No. 293,994, filed July 10,1963, now abandoned andentitled, Programming 'A-pparatus, now U.S. Patent 3,227,858, issuedJan. 4, 1966.

With the continual expansion of automated controls for system operation,emphasis is constantly being placed on component reliability. This hasresulted in the refinement of saturable reactors and other known controlcomponents and in the development of new control components suchas thesemiconductor family. Both the reactor-and the semiconductor componentsreliability is enhanced since there are no moving parts. Thisdevelopment to the present has concentrated on the component capable ofproviding a quick, complete response to an input signal..There has beena need .for a control component which is able to provide a prolongedoutput signal with varying characteristics in magnitude, shape, orrecovery time as desired and which is very reliable. This reliabilityhas again been attained in the present invention instance by thedevelopment of a device having no moving parts.'Further there has been aneed for'apparatus for providing an output signal proportional to, thenumber of events occurring. and the time spacing of such occurrences. 1

In the manufacture of silicon or siliceous fibers or filaments, such asglass fibers and the like, the glass to be formed is maintained in amolten state in electrically energized or heated .containers referred toas bushings. These bushings are typically energized to maintain themolten glass at a constant temperature in the order of approximately2300 F. durin g'the fiber forming operations. Usually the manufacturingoperation continues on a twenty-fourhour a day basis. Oftentimes theelectric power supply for energizing the bushing is cut olf due togenerating equipment failure or transmission line failure cause byaccumulation .of snow on the power lines, electrical storms, explosions,and other'unforeseen circumstances. These power failures may last forperiods of minutes toseveral hours, but generally the power is returnedon an average within a period of an hour.

During the time that the power supply is cut oif, the

Patented June 4, 1968 bushings gradually fall in temperature along anexponential decay curve from the operating temperature to ambienttemperature.

In the manufacture of glass fibers or other heat sofenable materials fortextile strands and the like there are the above-described inevitabletimes when the electrical power supplied to the textile bushing fails,resulting in loss of temperature in the textile bushing, and there areother times when the textile bushing is purposely shut down for cleaningof associated auxiliary equipment'or other maintenance. During thesetime the textile bushing temperature falls from the operatingtemperature of the bushing. When power is again applied to the textilebushing, it is of paramount importance that the power be applied at sucha rate as to avoid current surges damaging to the bushing while raisingthe temperature to operating range with a minimum loss of time. Thisrequires a control component capable of producing a prolonged outputsignal.

In another application a prolonged output signal with a desired varyingcharacteristic may be required in a trafiic control system. Still otherapplications for the programmer of this invention are in the field ofgenerating signal waves with certain desired characteristics and havingvery long wavelengths. A component has also been needed to integratesimultaneous or successive signals with a provision to take into accountthe time spacing of the signals or the time since the last signal. Suchcomponents are useful in elevator systems for integrating calls fromvarious floors being served by an elevator system and changing thesystem operation in accordance with the time-integration of such calls.Further, the component may be used in programming the time-sharing of atelephone system or of a single computer serving a number of controlloops.

Accordingly, it is an object of this invention to provide an impovedcontrol component or programmer.

It is another object of this invention to provide a reliable controlcomponent or programmer capable of sustained or prolonged outputs ofvarying characteristics.

A further object of this invention is to provide a reliable thermalcontrol component or programmer responsive to electrical input signalsand providing sustained electrical output signals.

One embodiment of the control component or programmer of this inventionincludes a heat accumulator device consisting of a resistor, a heatstoragedevice and associated heat insulation so selected that upondeenergization the temperature of the heat accumulator diminishesexponentially and substantially gradually over a desired period. Athermocouple is associated with the resistor and the heat storage deviceto sense the temperature and provide a signal in response thereto. Apower means or input signal means is selectively connected to cause theresistor to be heated. The heat storage device or heat sink will storethe heat or energy from the resistor. The thermocouple may be used toprovide an electrical output during the heat storage time and/or toprovide an electrical output after the heating of the resistor hasceased. This and other embodiments will be described in moredetail-hereinafter. I

It is thus a further object of the invention to provide programmingmeans to store information of electrically operating loads, and to usethe information stored to effect changes in operation.

In another embodiment, the invention features two heat sensors connectedin additive relationship, one disposed in thermal sensing relationshipwith an electrically operated load or heat generator while the other isdisposed in thermal sensing relationship with a heat accumulatingdesist-ance. The other or second heat sensor may then establish a signalin the one or first heat sensor as the temperature of the heataccumulating resistance is raised by supply of power from .a separatepower source. The time characteristic of such an accumulator isdependent upon the physical design of the resistance, its mass, and itswattage per square inch of heat dissipation. The total timecharacteristic of the accumulator is also dependent upon the kind,amount, :and placement of insulation, and is also dependent on the kind,mass and position of the heat sink-associated with the resistance beingheated.

'In a still further embodiment or application the invention herein isutilized as a time responsive integrating unit and comprises a heat sinkmeans for accumulating heat, means for applying heat to the heat sinkmeans in response to signals proportional to changes being measuredexternal to the unit, and thermoelectric means disposed in heat sensingrelationship with and responsive to the heat sink means for providing anelectrical output signal proportional to the heat accumulated in theheat sink. The heat sink is advantageously isolated or insulated fromambient temperatures to hold the heat longer for a more sustained outputsignal. The heat applying means may be a resistance means connected toand responsive to receive and totalize a plurality of successive orsimultaneous electrical input signals by dissipating heat to the heatsink in proportion to the inputs received. The thermoelectr-ic means maybe a thermocouple means responsive to and operative to generate a signalin proportion to heat accumulated in the heat sink. The thermoelectricmeans may also be an element having a resistance variable in response toheat and an electrical output circuit connected to the variableresistance element and controlled thereby.

Other objects, features and advantages of this invention will becomeapparent when the following description is taken in conjunction with theaccompanying drawings, in which:

FIG. 1 is a schematic circuit diagram of an electrical system which maybe controlled by a programmer 'according to this invention;

FIG. 2 shows an illustrative arrangement of one embodiment of theprogrammer apparatus of this invention;

FIG. 3 is a temperature-time chart showing the characteristic curves ofthe electrically heated load of the system in FIG. 1 and of theprogrammer in FIG. 2;

FIG. 4 is a schematic diagram of a traffic control system which may becontrolled by a programmer according to this invention;

FIG. 5 shows an illustrative arrangement of a second embodiment of theprogrammer apparatus of this invention, which embodiment may be used inthe system shown in FIG. 4;

FIG. 6 is a schematic diagram of a telephone timecontrol system whichmay be controlled by a time responsive integrating unit of thisinvention;

FIG. 7 is a temperature-time chart showing characteristic curves of theintegrating unit utilized in FIG. '6;

'FIGS. 8 and 9 schematically illustrate an elevator system controlled bya time responsive integrating unit of this invention;

FIG. e10 schematically illustrates a system for timesharing a computeror other controller in accordance with the teachings of this invent-ion;and

FIG. '11 is a schema-tic illustration of another embodiment of theintegrating unit of this invention.

Referring now to FIG. 1, there is shown a molten glass container,textile bushing or feeder 10 for forming textile fibers 12 from moltenglass. The molten glass may be maintained at :a normal operatingtemperature of about 2300 F. The operating temperature is maintainedwithin the desired range by direct passage through the feeder 10 ofelectrical current supplied from a transformer 14 which is energized inresponse to control of a saturable core reactor 16 connected to powersupply terminals 18. Other suitable control means such as a siliconcontrolled rectifier may be used to control power supplied.

The textile fibers 12 are formed of the molten glass fed throughorifices 20 in the bottom of the feeder 10. The fibers 12 are gatheredtogether into a strand 22 by passage of the fibers over a gatheringmember 26 in a manner well known in the art. The fibers are suppliedwith sizing fluid at the gathering member 26 from a supply tube 28communicating with a source of sizing fluid in a known manner, but notshown here. The successively formed portions of the strand-22 are woundupon a package =30 by a winder unit 32 as the strand 22 is cause-d totraverse the package 30 by a spiral wire-type traverse mechanism 36. a

The feeder 10 receives glass marbles which are heated into molten formby the secondary single loop winding of the transformer 14. The heatingcurrent for the feeder '10 is derived from alternating current suppliedto the terminals .18, for example, from a 440 volt, 60 cycle source, notshown.

A programming system 40 includes an electrical circuit wit-h at leasttwo heat sensors or thermocouples 42, 44 in series with a temperaturecontroller 46 for maintaining the temperature of the feeder 10. Thethermocouple 42 senses the temperature of the feeder While thethermocouple 44 senses the temperature at the heat sink 71 of a heataccumulator which includes a storage or programming resistor 50.

Referring to FIG. 3, the temperature-time characteristic curve 54 of thefeeder 10 as the temperature of the feeder decreases due to powerfailure or temporary shut-down of the feeder for fin cleaning or thelike is sensed by the thermocouple 42. The temperature-timecharacteristic curves 56 of the programming resistor 50 and/or heat sink71 as the temperature increases due to current supplied thereto from abattery 60, such as a Burgess 1.25 v. battery, is complementary orinverse with respect to the curve 54, as shown in FIG. 3.

As is apparent from the circuit arrangement of the programming system40, the resistor 50 is energized when the power supply at terminals 18fails or is shut down, since deenergization of relay 62 allows contacts64 to close to complete circuit 50, 60, 64.

The programming resistor 50 is imbedded in an insulating material 68such as glass fiber and the mass of insulation with the imbeddedresistor 50 and thermocouple 44 is encased in a housing 70. Thetemperature-time characteristics of the assembly are such that uponde-energization of the resistor 50, which occurs when power is againapplied to terminals 18 resulting in energization of the relay 62 toopen the contacts 64, the heat of the resistor 50 as sensed bythermocouple 44 diminishes exponentially gradually over a period of timelogarithmically proportional to the period of time that the resistor 50was energized. Thermocouple 44 therefore provides a signal additivelycombined with the signal derived in the feeder thermocouple 42 whereby acombined or control temperature signal is provided in controller 46 forregulating the magnitude of power that the saturable core reactor 16will allow the transformer 14 to supply to the feeder 10 and the rate atwhich the temperature of the feeder 10 may be raised during there-energization of the feeder while the programming resistor isdecreasing in temperature.

When generally complementary curves 54, 56 are provided, the seriesarrangement of thermocouples 42, 44

causes controller 46 to receive a substantially constant signal with aconsequent supply of constant power to the terminals 18 duringthestartupperiod of the feeder. Accordingly,,the current flow through the feederwhich would otherwise be a surge, will be restrained to a substantiallyconstant value during startup, thereby eliminating the need for tediousand randomly inaccurate manual regulation of the feeder.

Instead of a surge of current being directed through thefeeder ascalledfor by thermocouple 42 sensing a cold feeder, the programmer provides acomplementary prolonged or sustained control signal in thermocouple 44so that the feeder temperature appears apparently higher than itactually is in regulating the saturable core reactor 16. Accordingly,the controller. 46 restrains the current flow in the saturable corereactor from the terminals 18 to the feeder 10, while the temperature ofthe feeder is being continually built up. correspondingly, the

' feeder thermocouple 42 gradually develops an increased controllingsignal as the influence of the resistor or programmer thermocouplevdiminishes.

' The housing 70 in FIG. 2 may be generally configured to resemble whatis known as a pill box having a closure 72 that completes the enclosureof the imbedded resistor 50.and the thermocouple 44..A copper tube 71 isprovided as a heat sink to store the heat or energy dissipated by theresistor. Other devices may be used for heat storage, for example, ironpipe fittings. The heat storage device is an important factor indetermining the time-temperature curve of the programmer.

All the connections for the thermocouple to lead wires 73 may be softsolder heater wire connections which subsequent to forming theconnections are wrapped with strips of tape 74. A tape 75 which isadvantageously heat resistant may be interposed between the resistor 50and the thermocouple 44, and additional wrapping of preferably heatresistant tape-76 may be applied to cover the thermocouple and fill thetube 71 as shown in 'FIG. 2.

It is possible within the scope of the invention to provide one or moreadditional thermocouples that may be connected in parallel or series, asdesired, to provide other time-temperature characteristics that may bedesired.

Referring to FIGS. 4 and 5 there is shown in FIG. 4 a trafiic controlsystem, and in FIG. 5 a second embodiment of a programmer according tothis invention and suitable for use in the system of FIG. 4.

In the schematic traflic control circuit of FIG. 4 there is shown anintersection of two streets, AvenueX and First Street. The trafiic flowon the two streets is controlled by a signal light system 200. Detectors100 and 110 are placed along First Street, for example, half way downthe block from the intersection of First Street and Avenue X to sensethe trafiic flow along First Street. In response to traffic fiow thedetectors 100 and 110 send signals along connections 101 and 111, whichare proportional to the traffic flow, to a power control unit 120. Thesignals sent along leads 101 and 111 maybe proportional in amplitude ofvoltage or current or in the frequency of pulses. There are severalmechanisms that aresuitable for use as detectors such as the trafficcounters operated by air pressure and having an air hose stretchedacross the street, the photo-sensitive detectors which are operated bythe breaking of a light beam directed across the street,

etc.

The power control unit 120 via connection 121 controls a power supplyunit 130. The power supply unit 130 provides a signal to the input ofprogrammer 170 via connection l3lsproportional to. traffic flow alongFirst Street and of sufficient power to energize a resistor-150 forheating within programmer 170. Programmer170 provides an output viaconnection 173 to an amplifier 180. The amplifier 180 amplifies thesignal from programmer 170 and, via connection 181, provides a signal toa signal lightcontrol unit 190. The unit. 190 controls the indicatorlights 200 via connection 191 in a manner well known in the art.

In one embodiment of the schematic traflic control circuit of FIG. 4 thesignal lights may always be maintained on or green for the same amountof time for Avenue X. Depending upon the signal received from programmer170 the signal lights may allow trafiic flow from First Street throughthe intersection for the same amount of time as that flowing from AvenueX. As traflic increases along First Street detectors and sense thetrafiic increase, increase the signal from programmer 170, and :thusincrease the amount of time the signal light stays on or green to allowtraflic flow from First Street across Avenue X. I

The programming resistor 150, as shown in FIG. 5, is imbedded in aninsulating material 168, such as glass fiber, and the mass of insulation168 with the imbedded resistor and the thermocouple means 144 is encasedin a housing 170. The temperature-time characteristics of the assemblyare such that upon deenergization of the resistor 150, in response to alack of input power or siganl from power supply unit 130, thetemperature of the resistor 150 as sensed by the thermocouple 144diminishes exponentially gradually over a period of time proportional tothe period of time that the resistor 150 was energized. That is, theresistor 150 has an operating curve similar to that shown by the curve56 in FIG. 3. When resistor 150 is heated the temperature of resistor150 rises in accordance with the curve 56 in FIG. 3 as long as theresistor 150 receives power from the detection and power control.

A copper tube, or other suitable fitting, is provided as a heat sink tostore the heat or energy dissipated by the resistor 150. When theresistor 150 is no longer ener gized the temperature-time characteristiccurve 56 of the programming resistor 150 and/ or heat sink 171diminishes exponentially gradually over a period of time proportional tothe period of time that the resistor 150 was energized. Thus theprogrammer will continue to supply a signal for a period of time to thetraffic control 190 to allow the signaling system 200 to continue todirect trafiic through the intersection from First Street until apredetermined lower level of traflic has been reached. Once the signalfrom programmer 170 falls below a predetermined magnitude the signallight control 190 will then cause the signaling system 200 to directtraffic along Avenue X through the intersection.

Again, all of the connections for the thermocouple to output lead wires173 may be soft solder heater wire connections which subsequent toforming the connections are Wrapped with strips of tape 174. A tape 175which is advantageously heat resistant may be interposed between theresistor 150 and the thermocouple 144, and additional wrapping of heatresistant tape 176 may be applied to cover the thermocouple and fill thetube or heat sink 171.

The programmer of FIG. 5 is distinguished from the programmer shown inFIG. 2 by the addition of a second heat sink 177 around and in thermaldisposition with the cold junctions covered by the tape 174 of thethermocouple 144. The second heat sink 177 is of substantially the samemass as first-mentioned heat sink 171. This compensates for ambienttemperature variations, since the change in ambient temperature mustchange the temperatures of the equal masses by the same amount. If thesecond heat sink is not utilized ambient temperature fluctuations maychange the cold junctions temperature more rapidly than the temperatureof the hot junctions at 144 since the normal millivoltage output of theprogrammer varies as the difierence of the temperatures of the hotjunctions and the temperatures of the cold junctions.

Referring to FIG. 6 there is illustrated a telephone system which may becontrolled by the programmer or integrating unit of this invention.There are phone systems in use today, particularly internal systems inlarger business organizations, wherein telephone calls may be madedirectly without going through the city exchanges that would norm-allybe involved. In order to insure that the best use is made of suchinternal systems many have signal means, such as a buzzer to note theend of a specified period of use, e.g. three minutes. The buzzer willeither override the conversation or will be a signal prior to automaticcutofi' at the end of the specified period. Such systems cannotdetermine whether that particular line is really needed for another callor not, but arbitrarily interrupts at the end of the period.

In FIG. 6 there is illustrated a system for overcoming thesedifiiculties. Assume that a plurality of phones 201,

202, 203, 204, are connected to share the same speech carrying line.Switching means, such as designated generally at 220, may be arranged toprovide an input signal from a battery or other voltage source 211 whena call is made. If no other calls were attempted on this same line thenthe input signal and the programmer 200 could be designed to allow alonger time period to elapse, e.g. six minutes, before an output fromprogrammer 200 through amplifier 205 would be of a magnitude to initiateaction by the buzzer control system 207, thereby terminating the callfrom phone 201. That is, the heat accumulated in programmer orintegrating unit 201 would reach a predetermined level in response tothe electrical input signal from battery 211 and switching means 220 toprovide the desired output.

If calls were attempted by dialing any of the phones 202, 203, 204,switching means responsive to the dialing would be operative to providean additional input to the programmer 200. This would cause thepredetermined level of heat accumulated in the programmer 200 to bereached more quickly and in turn activate buzzer control system 207 morequickly, reducing the time of the call that may be made from phone 201.

The buzzer control system 207 may be set to provide a lower limit oftime, e.g. three minutes, no matter how many other calls are attemptedfrom the remaining plurality of phones on the line. However, theprogrammer would continue to accumulate heat in response to the callsattempted and, since the heat is dissipated from the heat sinkexponentially over a period of time, would continue to regulate thelength of the calls in response to the traflic on the phone line.

The range of design dimensions of the programmer 200 allows the use ofmany refinements. Various biasing means may 'be utilized. Clock timingmeans 230 may be used to bias the programmer 200 for a specified lengthof time during a selected period. That is, a 24 hour clock 231 may haveits drive mechanism connected to close a circuit between a movablecontact 232 and a stationary bar-type contact 233, for example, betweenthe normal business hours of 8:00 am. and :00 pm, or, on the 24 hourclock, 0800 hours and 1700 hours. The closure of contacts 232 and 233would provide a signal from source 234 through disabling switching means235 to the programmer 200. This would provide a base or bias level inputof heat to the accumulator or sink per the curve 236 illustrated in thetemperature-time graph of FIG. 7. The

curves shown in dotted lines represent other inputs to the programmer200, which would build the accumulated heat to the level necessary toinitiate the desired action. The switching means 235 may be utilized todisable the clock biasing input on days that are not regular work daysor this may be done automatically.

Similarly, a bias may be applied at will via a switch 235 and source239' to etfect other changes. It should be noted that a bias may beapplied after the programmer 200 or the amplifier 206 if it is desiredto accomplish an instantaneous bias that can be switched on or offwithout elfecting the heat build up and thus also the heat dissipationin the irogrammer 200. Such a biasing means could be the simple switch236 and source 239 network shown, connected before or after theamplifier 206.

Referring to FIGS. 8 and 9 there is shown an elevator system that may becontrolled by a programmer 240. In FIG. 8 there is illustrated circuitryfor registering floor calls for a plurality of fioors. Push buttons PBl,PB2, PB9, when pushed, close a circuit between power leads L1 and L2through their respective floor call relays FCI, FCZ, FC9. Contacts FCl,FC2, FC9 then close a circuit around the push buttons PBl, PB2, PB9, toprovide a holding circuit for the floor call relays FCl, FCZ, .FC9,until the calls are answered. Limit switches LS1, LS2, LS9, areoperative to be mechanically, electrically, or magnetically opened, asby a car door opening, When a car stops at a floor to answer a call. Theholding circuit at the floor where the 'call is answered is thus brokenand the circuit is ready to register a new call when a passenger wishesto use the elevator.

Although the floor call relays have many other contacts serving otherpurposes in a standard elevator system there is shown in FIG. 9 onecontact of each relay FCl, FC2, FC9, which are used to provide a signalfrom sources 251, 252, 253, respectively, to the programmer 240. As iswell known in the art the number of calls registered and the length oftime the calls have been registered constitutes information that is mostuseful in automatically determining the mode of operation of an elevatorsystem. That is, a bank of elevator cars may be zoned in theiroperation, overdue calls may be answered first, individual cars that aretemporarily parked may be put into operation again, etc. through theoperation modes that are most suitable for the traffic pattern of aparticular building being served by the system. For this particularexample the programmer has been used to integrate the number and lengthof time of registration of the calls to, for example, bring intooperation foff-duty cars that have been put into a stand-by or 011parking status because of low traflic demand. In response to inputs fromthe sources 251, 252, 253, the programmer 240 will accumulate more andmore heat to provide a larger output which may be used to bring one ormore additional cars back into operation.

Since the heat accumulated does not dissipate instantaneously theprogrammer 240 also serves to hold the extra cars in operation for awhile after the predetermined level has been reached so that new callsmay be answered speedily. Further, as the magnitude of the output fromthe programmer 240 drops the cars may be retired to their off-dutystatus in the reverse order and timing to that of their activation.

As discussed hereinbefore, biasing means may be utilized. Clock timingmeans 250 may be used to bias the programmer for anticipated rush hours,as at the begin ning and end of a working day and during a lunch hour. A24 hour clock 251 may have its drive mechanism connected to close acircuit between a movable contact 252 and a series of stationarycontacts 253, 254, and 255 positioned to cover peak trafiic hours 0800to 1000 hours, 1200 to 1300 hours and 1600'to 1800 hours. Closure of themovable contact 252 with any of the stationary contacts 253, 254, or 255would provide a bias signal for programmer 240 from source 256 viadisabling switching means 257 and would thus activate otf-duty cars. Theswitching means 257 could be utilized to disable the biasing means onthe week-ends when not needed. Additional selective biasing may beutilized for other purposes.

Referring to FIG. 10 there is illustrated schematically a system fortime-sharing a master programmer or a computer or other controlapparatus. A plurality of sensors 261, 262, and 263 are connected tomeasure changes in conditions being controlled. These conditions may beinputs to a process, calls registered in an elevator system, etc. Themagnitude, number of occurrences, and time of each occurrence will betranslated into'heat accumulation within programmers or integratingunits 271, 272 and 273, as received from sensors 261, 262, and 263,respectively.

The outputs of programmers or integrating units 271, 272,273, arecompared by comparison circuits 281'. Such comparison circuits can beset. to choose the highest, lowest, or closest to a predeterminedvaluefrom .the outputs of programmers 271, 272, and 273, and energize one ofthe corresponding relays SS1, SS2, SS3. Energization ofa relayclosescorresponding SS contacts on each side of the computer, masterprogrammer or control apparatus 280. When used with a computer this mayselect'a loop or channel in aprocess for immediate computation'of anadjustment signal for a variable in the process. If the programmer ispart of an elevator system a car may be selected and sent to a floorwhere a call has been registered for an abnormal length of time becausethe floor has been bypassed with express cars, cars already completelyloaded, etc. With control apparatus generally a particular mode ofoperation may be selected or a readout may be made.

Referring to FIG. 11 there is illustrated another embodiment of athermal programmer 300. A resistance or other means 301 and athermoelectric element T1 are placed in thermal disposition with respectto a heat sink or accumulator means 304. The heat sink means 304 isadvantageously thermally isolated or insulated from ambient temperaturesby insulating means 305. Input signals to the programmer or integratingunit are applied to heating means 301 via input terminals 302, 303.

The thermoelectric element T1 is an element having a resistance thatvaries substantially in response to heat, preferably one that has aninverse ratio. That is, as the heat applied rises, the resistance of theelement decreases. A thermistor is a suitable element for use in thisapplication. An electrical output circuit is to be connected in circuitwith the element T1 to provide the desired output signal. Although onlya single circuit including a source 306 and a current limiting resistorCLR is shown in FIG. 11 to provide an output to terminals 307, 308, itis to be noted that the element T1 may be utilized to control moresophisticated output circuitry such as solid state amplifying circuits.

The embodiment shown in FIG. 11 may be preferable in applications wherean output of substantial magnitude is required. The embodiments shown inFIGURES 2 and 5 may be preferred where smaller output signals aresuitable since the thermocouples utilized in those embodimentsconstitute self-sufiicient signal generating means requiring noadditional power pack.

In operation the apparatus of FIG. 11 is adapted to accumulate heat insink 304 in response to input signals received at terminals 302, 303.The thermoelectric means, including element T1 and the output circuit ofsource 306 and resistance CLR is operative to provide an output signalat terminals 307 and 308 proportional to the heat accumulated in sink104.

There has thus been described a thermal programmer or time responsiveintegrating unit which is capable of providing a sustained or prolongedoutput signal long after the input signal has ceased. It is obvious thatthe characteristics, magnitude and shape of the output signal may bechanged by utilizing additive combinations of thermoelectric sensingdevices and varying their relative dispositions with respect to thedevice being heated by the input signals. Further, varying the mass anddisposition of the heat sinks will affect the output signal.

In conclusion, it is pointed out that while the illustrated examplesconstitute practical embodiments of my invention, I do not limit myselfto the exact details shown since modification may be made withoutdeparting from the spirit and scope of this invention.

I claim:

1. A time responsive control unit comprising heat sink means foraccumulating heat; means for insulating said accumulating means fromambient temperatures; means for applying heat to said accumulating meansin response to signals proportional to conditions being measuredexternal to said unit; and means disposed in heat sensing relationshipwith said accumulating means and insulated from ambient temperatures tobe responsive only to 'said accumulating means for generating anelectrical output signal proportional to the amount of heat accumulatedtherein.

2. A control unit as defined in claim 1 in which said heat applyingmeans is a resistance means connected to and'respousive to receive andtotalize a plurality of electrical inputsby dissipating heat to saidaccumulating means in proportion to said input received.

3. A control unit as defined in claim 1 in which said generating meanscomprises thermocouple means responsive to and operative to generate asignal in proportion to heat accumulated in said accumulating means.

4. A control unit as defined in claim 1 which further includes means forbiasing said heat accumulating means to a predetermined temperaturelevel.

5. A control unit as defined in claim 2 which further includes means forapplying an input bias signal to said resistance means.

'6. A control unit as defined in claim 5 which further includes timingmeans and means responsive to said timing means for selectivelyconnecting said bias signal to said resistance means.

7. Apparatus for providing an output signal proportional to the numberof events occurring and the timespacing of such occurrences comprisingmeans for sensing each occurrence and the length of time of saidoccurrence and providing a signal proportional thereto, heat sink meansfor accumulating means responsive to said occurrence signals for heatingsaid heat accumulating mean-s, and means disposed in heat sensingrelationship with said heat accumulating means for generating anelectrical output signal proportional to the accumulated heat therein.

8. Apparatus as defined in claim 7 which includes a plurality of saidmeans for providing an output signal proportional to the number ofevents occurring and the time-spacing of such occurrences, and whichfurther includes means for comparing the magnitudes of said plurality ofoutput signals to select a predetermined program.

9. A thermal programmer comprising a device adapted to be heated withelectrical input signals, first means for storing the heat dissipated inresponse to said input signals, thermocouple means disposed intemperature sensing relationship with said first means, means forinsulating said temperature sensing disposition of said thermocouplemeans from ambient temperatures, said thermocouple means having coldjunctions, a second means of substantially the same mass as saidfirst-mentioned means disposed within said insulating means and inthermal relationship with said cold junctions of said thermocouple meansthereby providing compensation for ambient temperature changes externalof said insulating means, and output signal connections for saidthermocouple means.

10. A thermal programmer comprising a heat accumulator includinginsulating material having a device imbedded therein adapted to beheated with electrical input signals, first means imbedded in saidinsulating material and substantially surrounding said device to beheated to store the heat dissipated from said device, thermocouple meansdisposed in said accumulator in temperature sensing relationship withsaid 'device to be heated'and said first imbedded means, ambienttemperature compensating means comprising second means imbedded in saidinsulating material of substantially the same mass as said firstimbedded means and disposed in thermal relationship with cold junctionsof said thermocouple means, said thermocouple means providing anelectrical output signal proportional in magnitude to the heat presentin said accumulator.

11. A thermal programmer as defined in claim 10 in which said device tobe heated includes an electrical resistance.

12. A thermal programmer as defined in claim 11 'in 3,109,910 11/1963Fogleman 219-505 which said imbedded means are formed from metal tubes.3,227,797 1/1966 Rees 136 3,227,858 1/1966 Rees 219494 References CitedUNITED STATES PATENTS 5 OTHER REFERENCES 10/1943 Pearson AnalogueComputation, McGraw-Hill, vol. 3, Fifer Y 9/1953 Jacobsen et a1. 338-2213232?) 52222535333533: 3332i? RICHARD WOOD, Primary Dyer et a1 219-50410 L. H. BENDER, Assistam Examiner.

